In this work, we performed 3D numerical simulations in the framework of the Immersed Boundary - Lattice Boltzmann method to investigate the dependency of the TB-TT transition on the membrane viscosity \(\mu _{\mbox{\scriptsize m}}\)  for a single RBC. We studied the transition region, i.e., the region in the phase space \((\text{Ca},\lambda )\)  where the dynamics is neither pure TB nor pure TT: in particular, in this region we found an initially TB dynamics which switches to TT; the contrary, i.e., a TT that switches to a TB, has never been observed (in agreement to [1]}, [2]}). In particular, Cordasco et al. [3]} highlighted that the intermittent dynamics in the transition region depends on the stress-free configuration of the membrane, and for the biconcave discocyte shape they did not observe intermittency (while it was observed for a stress-free state close to a sphere).
